So, for a size 36 BiG says it will shrink down from a 39 to 36. But PBJ just mentions 37 inches (94.5=37).

What exactly is PBJ listing: what it measures raw (so it will shrink down one inch from 36 to 37), what it will measure down from 39 (39 to 37), or are they listing a one wash (even though it's listed as shrink-to-fit)?

I believe PBJ sell their jeans one wash to everyone but BiG, because folks in the US enjoy putting cardboard rigid pants in their bathtub so they can put pictures of the "process" on the internet. So I assume their measurements are for one wash.

I believe PBJ sell their jeans one wash to everyone but BiG, because folks in the US enjoy putting cardboard rigid pants in their bathtub so they can put pictures of the "process" on the internet.
So I assume their measurements are for one wash.

I believe PBJ sell their jeans one wash to everyone but BiG, because folks in the US enjoy putting cardboard rigid pants in their bathtub so they can put pictures of the "process" on the internet.
So I assume their measurements are for one wash.

Yes, the measurements are one wash and for most part PBJs flagshop only stocks one wash denim.